GCTC-NTGC / TalentCloud

import { useCallback, useEffect, useState } from "react";

import { useSelector } from "react-redux";

import { DispatchType } from "../configureStore";

import { RootState } from "../store/store";

import { getAwardRecipientTypes as fetchAwardRecipientTypes } from "../store/AwardRecipientType/awardRecipientTypeActions";

import { getAwardRecipientTypes } from "../store/AwardRecipientType/awardRecipientTypeSelector";

import { getAwardRecognitionTypes as fetchAwardRecognitionTypes } from "../store/AwardRecognitionType/awardRecognitionTypeActions";

import { getAwardRecognitionTypes } from "../store/AwardRecognitionType/awardRecognitionTypeSelector";

import { getEducationTypes as fetchEducationTypes } from "../store/EducationType/educationTypeActions";

import { getEducationTypes } from "../store/EducationType/educationTypeSelector";

import { getEducationStatuses as fetchEducationStatuses } from "../store/EducationStatus/educationStatusActions";

import { getEducationStatuses } from "../store/EducationStatus/educationStatusSelector";

import {

  AwardRecipientType,

  AwardRecognitionType,

  EducationType,

  EducationStatus,

  Job,

  Experience as ExperienceType,

  Skill,

  ExperienceSkill,

  ApplicationNormalized,

  Criteria,

  JobPosterQuestion,

  JobApplicationAnswer,

  Application,

  User,

} from "../models/types";

import {

  getApplicationById,

  getApplicationIsUpdating,

  getApplicationNormalized,

  getJobApplicationAnswers,

  getJobApplicationSteps,

  getStepsAreUpdating,

} from "../store/Application/applicationSelector";

import {

  fetchApplication,

  touchApplicationStep,

} from "../store/Application/applicationActions";

import {

  getCriteriaByJob,

  getJob,

  getJobIsUpdating,

  getJobPosterQuestionsByJob,

} from "../store/Job/jobSelector";

import { fetchJob } from "../store/Job/jobActions";

import {

  ApplicationStatusId,

  ApplicationStep,

  ApplicationStepId,

  ProgressBarStatus,

} from "../models/lookupConstants";

import {

  getExperienceByApplicant,

  getExperienceByApplication,

  getExperienceSkillsByApplicant,

  getExperienceSkillsByApplication,

  getUpdatingByApplicant,

  getUpdatingByApplication,

} from "../store/Experience/experienceSelector";

import {

  fetchExperienceByApplicant,

  fetchExperienceByApplication,

} from "../store/Experience/experienceActions";

import { getSkills, getSkillsUpdating } from "../store/Skill/skillSelector";

import { fetchSkills } from "../store/Skill/skillActions";

import { getUserById } from "../store/User/userSelector";

import { fetchUser } from "../store/User/userActions";

export function useUser(userId: number | undefined): User | null {

  return useSelector((state: RootState) =>

    userId ? getUserById(state, { userId }) : null,

  );

}

export function useApplication(

  applicationId: number,

): ApplicationNormalized | null {

  return useSelector((state: RootState) =>

    getApplicationNormalized(state, { applicationId }),

  );

}

export function useReviewedApplication(

  applicationId: number,

): Application | null {

  return useSelector((state: RootState) =>

    getApplicationById(state, { id: applicationId }),

  );

}

export function useJob(jobId: number | undefined): Job | null {

  return useSelector((state: RootState) =>

    jobId ? getJob(state, { jobId }) : null,

  );

}

export function useExperienceConstants(): {

  awardRecipientTypes: AwardRecipientType[];

  awardRecognitionTypes: AwardRecognitionType[];

  educationTypes: EducationType[];

  educationStatuses: EducationStatus[];

} {

  const awardRecipientTypes = useSelector(getAwardRecipientTypes);

  const awardRecognitionTypes = useSelector(getAwardRecognitionTypes);

  const educationTypes = useSelector(getEducationTypes);

  const educationStatuses = useSelector(getEducationStatuses);

  return {

    awardRecipientTypes,

    awardRecognitionTypes,

    educationTypes,

    educationStatuses,

  };

}

export function useSkills(): Skill[] {

  return useSelector(getSkills);

}

export function useCriteria(jobId: number | undefined): Criteria[] {

  return useSelector((state: RootState) =>

    jobId ? getCriteriaByJob(state, { jobId }) : [],

  );

}

export function useExperiences(

  applicationId: number,

  application: ApplicationNormalized | null,

): ExperienceType[] {

  const applicantId = application?.applicant_id ?? 0;

  // When an Application is still a draft, use Experiences associated with the applicant profile.

  // When an Application has been submitted and is no longer a draft, display Experience associated with the Application directly.

  const useProfileExperience =

    application === null ||

    application.application_status_id === ApplicationStatusId.draft;

  // This selector must be memoized because getExperienceByApplicant/Application uses reselect, and not re-reselect, so it needs to preserve its state.

  const experienceSelector = useCallback(

    (state: RootState) =>

      useProfileExperience

        ? getExperienceByApplicant(state, { applicantId })

        : getExperienceByApplication(state, { applicationId }),

    [applicationId, applicantId, useProfileExperience],

  );

  const experiencesByType = useSelector(experienceSelector);

  const experiences: ExperienceType[] = [

    ...experiencesByType.award,

    ...experiencesByType.community,

    ...experiencesByType.education,

    ...experiencesByType.personal,

    ...experiencesByType.work,

  ];

  return experiences;

}

export function useExperienceSkills(

  applicationId: number,

  application: ApplicationNormalized | null,

): ExperienceSkill[] {

  // ExperienceSkills don't need to be fetched because they are returned in the Experiences API calls.

  const applicantId = application?.applicant_id ?? 0;

  const useProfileExperience =

    application === null ||

    application.application_status_id === ApplicationStatusId.draft;

  const expSkillSelector = (state: RootState) =>

    useProfileExperience

      ? getExperienceSkillsByApplicant(state, { applicantId })

      : getExperienceSkillsByApplication(state, { applicationId });

  const experienceSkills = useSelector(expSkillSelector);

  return experienceSkills;

}

export function useJobPosterQuestions(

  jobId: number | undefined,

): JobPosterQuestion[] {

  return useSelector((state: RootState) =>

    jobId ? getJobPosterQuestionsByJob(state, { jobId }) : [],

  );

}

export function useJobApplicationAnswers(

  applicationId: number,

): JobApplicationAnswer[] {

  return useSelector((state: RootState) =>

    getJobApplicationAnswers(state, { applicationId }),

  );

}

export function useApplicationUser(applicationId: number): User | null {

  const application = useApplication(applicationId);

  const user = application?.applicant?.user ?? null;

  return user;

}

/**

 * Return all skills from the redux store, and fetch the skills from backend if they are not yet in the store.

 * @param dispatch

 */

export function useFetchSkills(dispatch: DispatchType): Skill[] {

  const skills = useSelector(getSkills);

  const skillsUpdating = useSelector(getSkillsUpdating);

  useEffect(() => {

    if (skills.length === 0 && !skillsUpdating) {

      dispatch(fetchSkills());

    }

  }, [skills.length, skillsUpdating, dispatch]);

  return skills;

}

/**

 * Return all Experience constants from the redux store, and fetch them from backend if they are not yet in the store.

 * @param dispatch

 */

export function useFetchExperienceConstants(

  dispatch: DispatchType,

): {

  awardRecipientTypes: AwardRecipientType[];

  awardRecognitionTypes: AwardRecognitionType[];

  educationTypes: EducationType[];

  educationStatuses: EducationStatus[];

} {

  const awardRecipientTypes = useSelector(getAwardRecipientTypes);

  const awardRecipientTypesLoading = useSelector(

    (state: RootState) => state.awardRecipientType.loading,

  );

  useEffect(() => {

    if (awardRecipientTypes.length === 0 && !awardRecipientTypesLoading) {

      dispatch(fetchAwardRecipientTypes());

    }

  }, [awardRecipientTypes, awardRecipientTypesLoading, dispatch]);

  const awardRecognitionTypes = useSelector(getAwardRecognitionTypes);

  const awardRecognitionTypesLoading = useSelector(

    (state: RootState) => state.awardRecognitionType.loading,

  );

  useEffect(() => {

    if (awardRecognitionTypes.length === 0 && !awardRecognitionTypesLoading) {

      dispatch(fetchAwardRecognitionTypes());

    }

  }, [awardRecognitionTypes, awardRecognitionTypesLoading, dispatch]);

  const educationTypes = useSelector(getEducationTypes);

  const educationTypesLoading = useSelector(

    (state: RootState) => state.educationType.loading,

  );

  useEffect(() => {

    if (educationTypes.length === 0 && !educationTypesLoading) {

      dispatch(fetchEducationTypes());

    }

  }, [educationTypes, educationTypesLoading, dispatch]);

  const educationStatuses = useSelector(getEducationStatuses);

  const educationStatusesLoading = useSelector(

    (state: RootState) => state.educationStatus.loading,

  );

  useEffect(() => {

    if (educationStatuses.length === 0 && !educationStatusesLoading) {

      dispatch(fetchEducationStatuses());

    }

  }, [educationStatuses, educationStatusesLoading, dispatch]);

  return {

    awardRecipientTypes,

    awardRecognitionTypes,

    educationTypes,

    educationStatuses,

  };

}

export function useJobApplicationSteps(): {

  [step in ApplicationStep]: ProgressBarStatus;

} {

  return useSelector(getJobApplicationSteps);

}

/**

 * Dispatches an api request that will record the step as touched, setting it to "complete" or "error",

 * and gets the validation status of the application steps.

 *

 * Returns true if the request is currently in progress, false otherwise.

 *

 * NOTE: this hook only runs once, when the component is first mounted.

 */

export function useTouchApplicationStep(

  applicationId: number,

  step: ApplicationStep,

  dispatch: DispatchType,

): boolean {

  const stepsAreUpdating = useSelector(getStepsAreUpdating);

  useEffect(() => {

    dispatch(touchApplicationStep(applicationId, ApplicationStepId[step]));

  }, [applicationId, step, dispatch]);

  return stepsAreUpdating;

}

/**

 * Return an Application (normalized, ie without Review) from the redux store, and fetch it from backend if it is not yet in the store.

 * @param applicationId

 * @param dispatch

 */

export function useFetchNormalizedApplication(

  applicationId: number,

  dispatch: DispatchType,

): ApplicationNormalized | null {

  const applicationSelector = (

    state: RootState,

  ): ApplicationNormalized | null =>

    getApplicationNormalized(state, { applicationId });

  const application: ApplicationNormalized | null = useSelector(

    applicationSelector,

  );

  const applicationIsUpdating = useSelector((state: RootState) =>

    getApplicationIsUpdating(state, { applicationId }),

  );

  const [applicationFetched, setApplicationFetched] = useState(false);

  useEffect(() => {

    if (application === null && !applicationIsUpdating && !applicationFetched) {

      setApplicationFetched(true);

      dispatch(fetchApplication(applicationId));

    }

  }, [application, applicationId, applicationIsUpdating, dispatch]);

  return application;

}

/**

 * Return an Application from the redux store, and fetch it from backend if it is not yet in the store.

 * @param applicationId

 * @param dispatch

 */

export function useFetchApplication(

  applicationId: number,

  dispatch: DispatchType,

): Application | null {

  const applicationSelector = (state: RootState): Application | null =>

    getApplicationById(state, { id: applicationId });

  const application: Application | null = useSelector(applicationSelector);

  const applicationIsUpdating = useSelector((state: RootState) =>

    getApplicationIsUpdating(state, { applicationId }),

  );

  useEffect(() => {

    if (application === null && !applicationIsUpdating) {

      dispatch(fetchApplication(applicationId));

    }

  }, [application, applicationId, applicationIsUpdating, dispatch]);

  return application;

}

/**

 * Return an Job from the redux store, and fetch it from backend if it is not yet in the store.

 * @param jobId

 * @param dispatch

 */

export function useFetchJob(

  jobId: number | undefined,

  dispatch: DispatchType,

): Job | null {

  const job = useJob(jobId);

  const jobUpdatingSelector = (state: RootState) =>

    jobId ? getJobIsUpdating(state, jobId) : false;

  const jobIsUpdating = useSelector(jobUpdatingSelector);

  useEffect(() => {

    // If job is null and not already updating, fetch it.

    if (jobId && job === null && !jobIsUpdating) {

      dispatch(fetchJob(jobId));

    }

  }, [jobId, job, jobIsUpdating, dispatch]);

  return job;

}

/**

 * Return all Experience relavant to an Application from the redux store, and fetch it from backend if it is not yet in the store.

 * @param applicationId

 * @param application

 * @param dispatch

 */

export function useFetchExperience(

  applicationId: number,

  application: ApplicationNormalized | null,

  dispatch: DispatchType,

): {

  experiences: ExperienceType[];

  experiencesUpdating: boolean;

  experiencesFetched: boolean;

} {

  const applicantId = application?.applicant_id ?? 0;

  // When an Application is still a draft, use Experiences associated with the applicant profile.

  // When an Application has been submitted and is no longer a draft, display Experience associated with the Application directly.

  const applicationLoaded = application !== null;

  const useProfileExperience =

    application === null ||

    application.application_status_id === ApplicationStatusId.draft;

  const experiences = useExperiences(applicationId, application);

  const experiencesUpdating = useSelector((state: RootState) =>

    useProfileExperience

      ? getUpdatingByApplicant(state, { applicantId })

      : getUpdatingByApplication(state, { applicationId }),

  );

  const [experiencesFetched, setExperiencesFetched] = useState(false);

  useEffect(() => {

    // Only load experiences if they have never been fetched by this component (!experiencesFetched),

    //  have never been fetched by another component (length === 0),

    //  and are not currently being fetched (!experiencesUpdating).

    // Also, wait until application has been loaded so the correct source can be determined.

    if (

      applicationLoaded &&

      !experiencesFetched &&

      !experiencesUpdating &&

      experiences.length === 0

    ) {

      setExperiencesFetched(true);

      if (useProfileExperience) {

        dispatch(fetchExperienceByApplicant(applicantId));

      } else {

        dispatch(fetchExperienceByApplication(applicationId));

      }

    }

  }, [

    applicantId,

    applicationId,

    applicationLoaded,

    dispatch,

    experiences.length,

    experiencesFetched,

    experiencesUpdating,

    useProfileExperience,

  ]);

  return {

    experiences,

    experiencesUpdating,

    experiencesFetched,

  };

}

/**

 * Return an User from the redux store, and fetch it from backend if it is not yet in the store.

 * @param jobId

 * @param dispatch

 */

export function useFetchUser(

  userId: number,

  dispatch: DispatchType,

): User | null {

  const user = useUser(userId);

  useEffect(() => {

    // If job is null and not already updating, fetch it.

    if (userId) {

      dispatch(fetchUser(userId));

    }

  }, [userId, dispatch]);

  return user;

}

}

/**

 * Trigger fetches for all data needed for the Application review process which is not yet in the redux store, or in the process of loading.

 * @param applicationId

 */

export function useFetchReviewApplicationData(

  applicantUserId: number,

  applicationId: number,

  jobId: number,

  dispatch: DispatchType,

): {

  applicationLoaded: boolean;

  jobLoaded: boolean;

  experiencesLoaded: boolean;

  experienceConstantsLoaded: boolean;

  skillsLoaded: boolean;

} {

  const application = useFetchApplication(applicationId, dispatch);

  const job = useFetchJob(jobId, dispatch);

  const { experiences, experiencesUpdating } = useFetchExperience(

    applicationId,

    application,

    dispatch,

  );

  const {

    awardRecipientTypes,

    awardRecognitionTypes,

    educationTypes,

    educationStatuses,

  } = useFetchExperienceConstants(dispatch);

  const skills = useFetchSkills(dispatch);

  return {

    applicationLoaded: application !== null,

    jobLoaded: job !== null,

    experiencesLoaded: !experiencesUpdating || experiences.length > 0,

    experienceConstantsLoaded:

      awardRecipientTypes.length > 0 &&

      awardRecognitionTypes.length > 0 &&

      educationTypes.length > 0 &&

      educationStatuses.length > 0,

    skillsLoaded: skills.length > 0,

  };

}